1. Field of the Invention
The invention relates to an image based touch apparatus, and particularly relates to an image based touch apparatus using region indicators to mark a touch surface and a control method thereof.
2. Description of Related Art
With the rapid advancement of touch technology, the touch apparatus has become an essential apparatus in electronic devices, such as mobile phones, tablet personal computers, or portable multimedia players. The touch apparatus also replaces the traditional keyboard or physical buttons and has become a new-generation input apparatus. The common touch apparatus on the electronic devices includes a capacitive touch apparatus, a resistive touch apparatus, an optical touch apparatus, and so on.
According to the existing touch techniques, the touch apparatuses which have been designed, modified, manufactured, or set up to be touched by the operating object, such as smart phones or fixed-size touch screens on tablet personal computers, have been developed. However, the existing touch techniques cannot allow users to use the touch apparatuses at all times. For example, if the users are in the environment having only one blank wall, televisions with touch functions must be additionally installed, or projectors and projection screens capable of performing the touch functions need be installed before the touch functions are actually performed. Besides, the touch region of the touch apparatus is restricted by the size of the screen on the television, the projection range of the projector, and the size of the projection screen. Therefore, the application ranges of touch techniques can be expanded if apparatuses capable of adjusting the size of the touch regions can be developed.